Table 1.

Characteristics of the ideal biomarker.

■Easy to quantify in accessible clinical material ■Measurements are reliable, quick, reproducible, and cheap ■Abundance not subject to wide variation in the general population ■Reflects total burden of disease at all sites ■Expression specifically altered (elevated or reduced) in the relevant disease ■Unaffected by unrelated conditions and co-morbid factor ■Expression increased in the established disease without overlap between untreated patients and healthy subjects ■Variation of their concentration or activity in response to treatment which is closely correlated with established the clinic-pathological parameters of the disease